This is a dedicated VM which is never accessed for any reason except to perform maintenance, so the only realistic option is that either Linux screwed up or Graylog screwed up. I'll never know for sure.
Anyway, giving Elasticsearch folder permissions fixed it... What would have happened if I was unlucky and that search didn't turn up the result immediately?
Linux is not nearly as far ahead of Windows as we'd like to think. It has it's own bucket of jank, it's just a bucket of jank we prefer.
A single-user space station out in the fediverse asteroid belt.